Patent GB-682502-A (GB)
Title: Improvements relating to glass envelope manufacturing machines
IPC: H01J9/32
Filed: 1946-12-12
Abstract: 682,502. Discharge apparatus. SYLVANIA ELECTRIC PRODUCTS, Inc. Dec. 12,1946 [Dec. 12, 1945], No. 36735/46. Class 39(i) [Also in Group XXXVI] In a machine for joining a glass tube 4, Fig. 13. on to a glass disc 2 and moulding the latter around terminal pins 1 to make the end closure of a lamp valve or the like, spindles 8 carrying lower mould parts 15 are spaced around an intermittently rotated turret 7 which places each spindle in sequence at a Station A where pins 1 are placed in the mould 15, preparatory to the placing of the disc 2 on the mould, a station B where the pins are ejected if a disc has not been placed on the mould, a station C where the tube 4 is applied to the disc, a pre-pressing station D, a final moulding station E and a discharge station F. In Fig. 1 the spindles 8 are rotated, except in the disc supply zone between the stations A and B, by a chain 46 passing around the turret. The turret and the spindles are driven through gearing by a motor which also drives cam shafts for operating locking means for holding the turret at each period of rest, and for raising and lowering the upper mould members. The spindle drive includes a friction clutch 27 on each spindle, so that the spindle may be locked when necessary, against rotation. At the station A a number of hoppers 51, containing terminal pins, are each provided with a feed tube which leads a pin into an aperture in the lower mould part 15. The discs are pre-heated and placed by hand-tongs on the mould part 15 and over the pins 1 which project above the mould. At the station B, if a disc 2 has not been placed on the mould, a spring-pressed finger 59 will initiate the action of a pin unloader as described in Specification 646,644. Also an electric control will be set for functioning at station. E as described below. The work is heated during the intermittent movement of the moulds from B to C, by burners 61 carried by a segment 62 and fed with regulable gas, air and oxygen supplies. At station C where rotation of the spindle continues, a glass tube 4 is supplied from a hopper 67 by a carrier which turns it into an upright position for application to the disc 2, means, described below, being provided for maintaining the tube in axial alignment with the disc whilst it is fused thereto. At station D, the union of the stem and disc is made more secure, by means described below, before the work is subjected, at station E to the final moulding between upper and lower moulds. At the unloading station F, the work is cooled by air jets 54, and at G the mould 15 is sprayed to prevent adherence of glass thereto. Spindle and lower mould construction. The spindles 8 are journaled in ball bearings 9, 10, in flanges 11, 12 on the turret 7, and are driven by the chain 46 through sprockets 28 and clutches 27. Each spindle has a central bore in which is accommodated a hollow sleeve 24 and a central rod 19. The sleeve carries slender rods 22 which function as stops and knockouts for the pins 1 which are placed in aligned apertures 21 in the mould 15 and in a closure 14 for the upper end of the spindle 8. The mould 15 is removably secured in position by inturned segmental parts 16 of a sleeve 17. The spindle is held stationary, when necessary at a particular station, by a latch engaging a detent 30. The rod 19 is connected, by trunnions 81 on the outer race of a ball bearing 80, to a spring- pressed lever which normally keeps the tip 20 of the rod below the top of the mould 15, but which is engaged by segmental cam tracks 89 to raise the tip from the mould in which position it centres the tube 4 relatively to the disc 2 and maintains an opening through the tube. The lower end of the sleeve 24 is threaded into the inner race of a ball-bearing 90, the outer race being pressed into an arm 91 slidable, on a guide rod 92, by a roller 95 engaging an interrupted segmental cam track 98 whereby the sleeve 24, and the rods 22 drop at the pin-loading station A, then rise to permit the rods 22 to act as locating stops for the pins, fall to disengage the rods from the pins during the final moulding, and lastly rise to eject the pins from the mould at the unloading station F. Supplying and locating the tubes. At station C the spring-retractable arm 69 carries a tube 4 into alignment with the rod 19, the tube being carried past a spring actuated gate which opens to permit the tube to rest against the inner face of a segmental guide 99. The tube is retained against the guide 99 by a notch 107 in an arm 106 on a shaft 100 which is urged to the operative position by a spring 108 and to the inoperative position by a cam 105. The tubes are thus positioned by the means 99, 106 at one end, and by the rod 19 at the other. Preliminary pressing. At the stations C and D, press members 170, 179 operated by a common vertically reciprocating crosshead 151 and supported from a centre post 72 by an arm 74, bear down on the tubes 4 and set them firmly on to the disc 2 and rods 19. A vertical rod 148 carried by the arm 74 forms a guide for a sleeve 149 to which the crosshead 151 is secured, and the members 170, 179 are at the lower end of rods 153, 154 which are slidable in sleeves in a fixed crosshead 158. The rods 153, 154 are slidable against the action of springs in the crosshead 151 which is located by a slotted tail piece thereon being engaged by a pin depending from the arm 74. The press member 170, Fig. 15, is provided with a tube engaging member 169 having an upwardly directed stem 168 which is journaled for free rotation in a sleeve 164 to which the member 170 is screwed, thrust being taken by the ball 174. At station C the tube 4 is thus pressed on to the disc and permitted to rotate therewith. At station D the rod 154 is mounted for rotation, being connected by a shaft 191, gearing 187 and universal couplings to a sprocket pressed resiliently into engagement with the chain 46. The hub 184 of the last driven gear wheel is concentric with the rod 154 and has vertical slots 183 which are engaged by rollers 182a on a collar secured to the rod and providing an abutment for the spring 176. The rod 154 may thus be rotated during its vertical reciprocations which are effected by a rod 201 connected to the crosshead 151 and, at the other end, to a bell-crank operated by a rotary, cam. The press member 179 rotating at the same speed as the spindle 8, completes the centreing of the tube 4 on the disc without torsional strain, after which the turret is indexed to bring the work to station E. Final pressing. The upper mould part 53 is apertured at 225 to receive the pins 1 in the work piece, is carried on a vertical sliding compound rod 221, 222, the part 222 being axially bored to receive the tube 4 of the workpiece and the part 221 also being bored to accommodate a rod 226 which functions when a tube 4 breaks off within the bore, firstly to stop the machine, and secondly to knock out the broken glass. The stoppage is effected by the head 227 being lifted to release the contact spring 263 to close the circuit of a solenoid which controls the press. The final pressing means are carried by an arm 71 from the central post 72, the bracket 211 and attached parts 213, 214, 216, 217 for supporting the vertically slidable parts being radially adjustable by means 212. A sleeve 215, enclosing the rod 221, 222, is supported for vertical movement in oil-sealed bearings 213, 214 and is connected by a clamp 238 to cam-operated linkage 232, 236, including a shock absorber, whereby the mould part 53 is depressed on to or retracted from the mould part 15. The link 232 is tubular and is normally clutched by a pawl to an inner rod so as to move therewith. However, if a glass disc is absent at station B, the electric control set by the arm 59 now operates a solenoid to detach the pawl from the inner rod and instead to clutch the tubular link to a stationary part, whereby the inner rod is reciprocated idly, by the cam. The solenoid movement also cuts off the supply to the spray gun 261 which sprays the mould to prevent adherence of glass thereto. A micro-switch 265 carries a spring-pressed follower 266 engaged by an arm 267 on the clamp 238. This actuates a plunger 268 to set an electric control which, if the press fails in its upward stroke, stops the machine. An air jacket 269, having inlet and outlet pipes cools the apparatus adjacent to the mould part 53. A section of the tube guide 99 is swung away as the press descends and simultaneously, the tube supporting arm 106 carried by the spindle 8, is swung out of the way. Discharge of the work piece. During the passage of the work pieces to the discharge station F, the stems 4 are supported by the members 99, 106 whilst air is blown against the work by jets 54. The stems are gripped by fingers 75, Fig. 1, which lift the work pieces from the moulds 15 and, by means of a swinging arm 76, deposits them in a discharge shoot. Specification 646,643, [Group XI], also is referred to.